The effect of the high-fat diet on the work metabolism has been studied in twice on normal young man aged 25 years.
Method: The experimental diets are as shown in table 1. At first high-carbohydrate diet war provided for three days, and next high-fat diet for five days, and at last high-carbohydrate diet for two days, similarly in the first and second experiment. The contents of fat in high-fat diets were about 30 percent calories (100 grams of butter) in the first experiment and 50 percent calories (150 grams of butter) in the second experiment.
The muscular work was performed for 50 minutes at the pass of 3 hours after the morning meal by revolving the bicycle-ergometer. The amount of the muscular work performed is as in tabe 2. The collection of expired air during work and recovery period was conducted continuously by Douglas-Bag each for three or four minutes. And alkaline reserve of blood plasma was determined by Vanslyke-Cullen method and urinary excretion of acetone bodies by Behre' colorimetric method.
Results:
(1) The work metabolism in high-fat diet periods showed the decrease of CO2 production, accordingly of respiratory quotient and of the volume of expired air.
Even O2 consumption and heat consumption were slightly decreased compared with the work metabolism in high-carbohydrate diet periods. This phenomenon was remarkable specially in the case of fat diet containd 50 percent (Table 3 and 4, Figure 1). This aspect was also seen in tke basal metabolism and the resting metabolism (Table 7).
(2) Alkaline reserve of blood plasma declined slightly right after the work, but it recovered at the 30 minutes after the work (Table 8)
(3) Urinary acetone bodies had no difference between high-carbohydrate diet and fat diet containing 30 percent, but in 50 percent fat diet increased evidently (Table 9).
These results showed that high-fat died effected efficiently to the work metabolim, but 50 percent of fat in calorie seemed to be excessive for Japanese from the reason of increase of the urinary aceton bodies.
